I Was Diagnosed Today 1/2/17 With Walking Pneumonia Or Mycoplasma

I was diagnosed today 1/2/17 with walking pneumonia or mycoplasma pneumonia. I have had a dry cough and low grade fever for weeks. In that time I have visited my mother who is 89 and in a nursing home. How long have I been contagious? I always took precautions when visiting her by covering my mouth when I coughed and washing my hands all the time when I was with her.
Thank you. Karen